Don't worry, Makoto is about to get tossed into the battlefield.
That said this little arc is also an introduction to the demons.
The giant Io here is such a BRO that when Makoto fight him later, Makoto hesitates in killing him and even go as far as dispelling a magic Io used that would kill him quickly but also give him a massive stat boost (Makoto still beat him even with the boost)
The other demon of note is the strategist/tactician who planned the pit fall.
She's gonna be Makoto's introduction to 'yeah, even the demons can be jerks' and ironically push him into being less of a naive nice guy.